Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Preterm Infants Without Chronic Lung Disease or Congenital Heart Disease

. 2016 Sep 14;5(4):417–452. doi: 10.1007/s40121-016-0130-1

Summary box

	Level of evidence^a
Key statements/findings
Studies have shown that preterm infants, particularly those born at lower gestational ages, are at high risk for RSVH and tended to have higher rates of hospitalization for RSV compared with otherwise healthy term infants	1 (Level 1 studies: n = 8; risk of bias^b: 10.9)
RSVH rates for preterm infants ranged from >100 per 1000 children to ~5 per 1000, with the highest rates shown in the lowest gestational age infants	1 (Level 1 studies: n = 8; risk of bias^b: 11.0)
Compared to otherwise healthy/term infants, premature infants have Longer median hospital stays Increased complication rates Increased risk for ICU admission	1 (Level 1 studies: n = 9; risk of bias^b: 10.6)
A number of independent risk factors associated with RSVH in premature infants have been reported including exposure (e.g. proximity of birth to the RSV season, living with school-age siblings), social factors (e.g. smoking of mother during pregnancy or environmental smoking, reduced breast feeding), and biological factors (e.g. male sex, familial asthma)	1 (Level 1 studies: n = 6; risk of bias^b: 11.0)
Predictive models for RSVH in 32–35 wGA infants have been developed using 4 or 7 risk factors with areas under the ROC curves ranging from 0.687 to 0.791 (fair to good predictive accuracy)	1 (Level 1 studies: n = 6; risk of bias^b: 11.0)

Key areas for research
In light of the continuing burden and long-term sequelae of severe RSV infection in otherwise healthy preterm infants, further research is needed on gestation-specific prevalence and burden of RSV disease to confirm the vulnerability of these children
Further prospective studies should be undertaken to fully explore the changing risk of RSVH during the first year of life in preterm infants

ICU intensive care unit, ROC receiver operating characteristic, RSV(H) respiratory syncytial virus (hospitalization), wGA weeks’ gestational age

^aLevel 1: Local and current random sample surveys (or censuses); Level 2: Systematic review of surveys that allow matching to local circumstances; Level 3: Local non-random sample; Level 4: Case-series [26, 27]

^bAverage RTI Item Bank Score [28], where 1 = very high risk of bias and 12 = very low risk of bias